<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>欢迎注册</title>
    <link href="../css/register.css" rel="stylesheet">
</head>
<body>
<div class="form-div">
    <div class="reg-content">
        <h1>欢迎注册</h1>
        <span>已有帐号？</span> <a href="#">登录</a>
    </div>
    <form id="reg-form" action="#" method="get">
        <table>
            <tr>
                <td>用户名</td>
                <td class="inputs">
                    <input name="username" type="text" id="username">
                    <br>
                    <span id="username_err" class="err_msg" style="display: none">用户名不太受欢迎</span>
                </td>
            </tr>

            <tr>
                <td>密码</td>
                <td class="inputs">
                    <input name="password" type="password" id="password">
                    <br>
                    <span id="password_err" class="err_msg" style="display: none">密码格式有误</span>
                </td>
            </tr>

            <tr>
                <td>手机号</td>
                <td class="inputs"><input name="tel" type="text" id="tel">
                    <br>
                    <span id="tel_err" class="err_msg" style="display: none">手机号格式有误</span>
                </td>
            </tr>
        </table>
        <div class="buttons">
            <input value="注 册" type="submit" id="reg_btn">
        </div>
        <br class="clear">
    </form>

</div>


<script>
    //验证用户名是否复合规则
    var usernameInput = document.getElementById("username");
    //给该标签添加校验功能,给功能命名以便调用(把校验结果返回),匿名适用于不复用代码
    usernameInput.onblur = checkUsername;
    function checkUsername(){
        var username = usernameInput.value.trim();
        //使用正则简化部分省略
        var flag = username.length >= 6 && username.length <= 12;
        if(flag){
            document.getElementById("username_err").style.display = "none";
        }else{
            document.getElementById("username_err").style.display = "";
        }
        return flag;
    }

    //验证密码框规则
    var passwordInput = document.getElementById("password");
    passwordInput.onblur = checkPassword;
    function checkPassword(){
        var password = passwordInput.value.trim();
        var flag = password.length >=6 && password.length <= 12;
        if(flag){
            document.getElementById("password_err").style.display = "none";
        }else{
            document.getElementById("password_err").style.display = "";
        }
        return flag;
    }

    //验证手机号11位
    var telInput = document.getElementById("tel");
    telInput.onblur = checkTel;
    function checkTel(){
        var tel = telInput.value.trim();
        var flag = tel.length === 11;
        if(flag){
            document.getElementById("tel_err").style.display = "none";
        }else{
            document.getElementById("tel_err").style.display = "";
        }
        return flag;
    }

    //按下注册按钮的时候验证表单
    var regForm = document.getElementById("reg-form");
    //绑定onsumbit事件
    regForm.onsubmit = function (){
        var flag = checkUsername() && checkPassword() && checkTel();
        return flag;
    }
</script>
</body>
</html>